GSK-3β Research Articles

GSK-3β inhibition alleviates arthritis pain via reducing spinal mitochondrial reactive oxygen species level and inflammation.

Pain is the main symptom of osteoarthritis, which severely reduces the patients' quality of life. Stimulated neuroinflammation and elevated mitochondrial oxidative stress are associated arthritis pain. In the present study, arthritis model was established by intra-articular injection of complete Freund's adjuvant (CFA) on mice. Knee swelling, pain hypersensitivity and motor disability were observed in CFA-induced mice. In spinal cord, neuroinflammation was triggered and presented as severe infiltration of inflammatory cells and up-regulated expressions of glial fibrillary acidic protein (GFAP), nuclear factor-kappaB (NF-κB), PYD domains-containing protein 3 (NLRP3), cysteinyl aspartate specific proteinase (caspase-1) and interleukin-1 beta (IL-1β). Mitochondrial function was disrupted and characterized as elevated expressions of B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), dihydroorotate dehydrogenase (DHODH) and cytochrome C (Cyto C), and reduced expressions of Bcl-2 and Mn-superoxide dismutase (Mn-SOD) activity. Meanwhile, as a potential target for pain management, glycogen synthase kinase-3 beta (GSK-3β) activity was up-regulated in CFA induced mice. To explore potential therapeutic options for arthritis pain, GSK-3β inhibitor TDZD-8 was intraperitoneally injected for three days on CFA mice. Animal behavioral tests found that TDZD-8 treatment elevated mechanical pain sensitivity, suppressed spontaneous pain and recovered motor coordination. Morphological and protein expression analysis indicated that TDZD-8 treatment decreased spinal inflammation score and inflammatory related protein levels, recovered mitochondrial related protein levels, and increased Mn-SOD activity. In summary, TDZD-8 treatment inhibits GSK-3β activity, reduces mitochondrial mediated oxidative stress, suppresses spinal inflammasome response, and alleviates arthritis pain.

Investigation of Cyclo-Z Therapeutic Effect on Insulin Pathway in Alzheimer's Rat Model: Biochemical and Electrophysiological Parameters

Cyclo (his-pro-CHP) plus zinc (Zn+2) (Cyclo-Z) is the only known chemical that increases the production of insulin-degrading enzyme (IDE) and decreases the number of inactive insulin fragments in cells. The aim of the present study was to systematically characterize the effects of Cyclo-Z on the insulin pathway, memory functions, and brain oscillations in the Alzheimer's disease (AD) rat model. The rat model of AD was established by bilateral injection of Aβ42 oligomer (2,5nmol/10μl) into the lateral ventricles. Cyclo-Z (10mg Zn+2/kg and 0.2mg CHP/kg) gavage treatment started seven days after Aβ injection and lasted for 21 days. At the end of the experimental period, memory tests and electrophysiological recordings were performed, which were followed by the biochemical analysis. Aβ42 oligomers led to a significant increase in fasting blood glucose, serum insulin, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and phospho-tau-Ser356 levels. Moreover, Aβ42 oligomers caused a significant decrement in body weight, hippocampal insulin, brain insulin receptor substrate (IRS-Ser612), and glycogen synthase kinase-3 beta (GSK-3β) levels. Also, Aβ42 oligomers resulted in a significant reduction in memory. The Cyclo-Z treatment prevented the observed alterations in the ADZ group except for phospho-tau levels and attenuated the increased Aβ42 oligomer levels in the ADZ group. We also found that the Aβ42 oligomer decreased the left temporal spindle and delta power during ketamine anesthesia. Cyclo-Z treatment reversed the Aβ42 oligomer-related alterations in the left temporal spindle power. Cyclo-Z prevents Aβ oligomer-induced changes in the insulin pathway and amyloid toxicity, and may contribute to the improvement of memory deficits and neural network dynamics in this rat model.

The impact of sitagliptin in palmitic acid-induced insulin resistance in human HepG2 cells through the suppressor of cytokine signaling 3/phosphoinositide 3-kinase/protein kinase B pathway.

Patients with type 2 diabetes respond differently to sitagliptin, an oral anti-hyperglycemic medication. Patients whose blood sugar levels were effectively managed while using sitagliptin had significantly lower levels of a protein called suppressor of cytokine signaling 3 (SOCS3), according to our earlier research. In this study, we established an in vitro insulin resistance cell model for human HepG2 cells to investigate the possible mechanism of the effect of sitagliptin on glucose metabolism via the SOCS3/phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) pathway. Since insulin resistance first develops in the liver, palmitic acid was used to generate an insulin resistance cell model in human HepG2 cells, after which small interfering ribonucleic acid (siRNA)-SOCS3 and sitagliptin were used to intervene. We then examined the changes in cell viability and biochemical indices in the insulin resistance cell model. SOCS3, Akt, and glycogen synthase kinase 3beta (GSK-3β) gene expression levels were quantified using reverse transcription-polymerase chain reaction, and the protein expression levels of SOCS3, Akt, phosphorylated Akt (p-Akt), GSK-3β, and phosphorylated GSK-3β (p-GSK-3β) were quantified using Western blot. In results: the expression of the SOCS3 gene was considerably raised in both the insulin resistance model group and the insulin resistance model + siRNA-negative control group, but decreased following treatment with sitagliptin. After sitagliptin intervention, the protein expression of Akt, p-Akt, and p-GSK-3β were dramatically decreased in the model group, while SOCS3 was significantly decreased. We conclude that sitagliptin can reduce insulin resistance by downregulating SOCS3 and regulating glucose metabolism in a hypoglycemic manner.

Effect of Plantago asiatica L. extract on the anagen phase in human hair follicle dermal papilla cells.

The hair growth cycle consists of the anagen, catagen, and telogen phases, and hair follicle dermal papilla (HDP) cells of human hair play a role in the initiation and maintenance of the anagen phase. Reduction in HDP cells contributes to hair loss; however, the limited treatment options are associated with negative side effects. Therefore, a naturally derived substance with hair loss-preventing properties is needed. We investigated the hair growth-stimulating activities of Plantago asiatica L. extract (PAE) and its molecular mechanism in HDP cells. Cell proliferation was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide solution. Relative mRNA and protein expression levels of hair growth factors were determined using quantitative real-time polymerase chain reaction and western blotting, respectively. Additionally, a tube formation assay was performed in human umbilical vein endothelial cells (HUVEC). Plantago asiatica L. extract significantly increased the cell proliferation and expression of hair growth factors, including keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF), fibroblast growth factor 2 (FGF2) and MYC, in HDP cells. Moreover, PAE led to the accumulation of β-catenin by promoting the phosphorylation of glycogen synthase kinase-3 beta (GSK-3β) at Ser9 and cAMP response element-binding protein (CREB) at Ser133 via phosphorylation of extracellular signal-regulated kinase (ERK) (Thr202/Tyr204). PAE also increased tube formation in HUVECs, which promoted angiogenesis for the anagen phase. Plantago asiatica L. extract amplified tube formation and production of growth factors (KGF, VEGF) via the activation of GSK-3β/β-catenin and mitogen-activated protein kinase (MAPK)/CREB signaling pathways, demonstrating its potential to safely promote hair growth by inducing the anagen phase.

Evaluation of wound healing active principles in the transdermal patch formulated with crude bio wastes and plant extracts against GSK-3 beta - an in silico study

The wound-healing process is accelerated by inhibiting proteins that decelerate the wound-healing pathway. One of the active proteins involved in enhancing healing at the nuclear level and in gene expression is catenin. Inhibition of Glycogen Synthase Kinase 3β (GSK3 β) phosphorylates and degrades catenin via the downstream Wnt signalling pathway, thereby stabilizing catenin. A medicated wound dressing transdermal patch designed with fusion of bio wastes, viz. physiologically clotted fibrin, fish scale collagen, and the ethanolic extract of Mangifera indica (L.) and spider web, was analysed against GSK3β to enhance healing. In our earlier studies, the compounds present in the transdermal patch were identified using GC-MS analysis; 12 compounds exhibiting the wound healing mechanism were analyzed using PASS software and filtered out. From these 12 compounds, 6 compounds that possessed drug-likeness were screened by SwissADME and vNN-ADMET to dock against GSK3β in the present work. The PyRx results confirmed the binding of the six ligands to the active site of the target protein. Though the remaining filtered ligands also exhibited inhibitory activity, Molecular dynamics simulation studies were carried out with 100 ns on a complex of 10,12 Tricosadiyonic acid, Nopyl acetate and 2 Methyl 4 Heptanol as they showed binding affinity of −6.2Kcal/mol, −5.7Kcal/mol and −5.1Kcal/mol respectively. The stability of the complex was validated using MD simulation parameters RMSD, RMSF, Rg, and Number of Hydrogen bonds. These results implied that the transdermal patch would be efficient in accelerating the wound healing process through the inactivation of GSK3β. Communicated by Ramaswamy H. Sarma

Brain insulin resistance linked Alzheimer’s and Parkinson’s disease pathology: An undying implication of epigenetic and autophagy modulation

In metabolic syndrome, dysregulated signalling activity of the insulin receptor pathway in the brain due to persistent insulin resistance (IR) condition in the periphery may lead to brain IR (BIR) development. BIR causes an upsurge in the activity of glycogen synthase kinase-3 beta, increased amyloid beta (Aβ) accumulation, hyperphosphorylation of tau, aggravated formation of Aβ oligomers and simultaneously neurofibrillary tangle formation, all of which are believed to be direct contributors in Alzheimer's Disease (AD) pathology. Likewise, for Parkinson's Disease (PD), BIR is associated with alpha-synuclein alterations, dopamine loss in brain areas which ultimately succumbs towards the appearance of classical motor symptoms corresponding to the typical PD phenotype. Modulation of the autophagy process for clearing misfolded proteins and alteration in histone proteins to alleviate disease progression in BIR-linked AD and PD have recently evolved as a research hotspot, as the majority of the autophagy-related proteins are believed to be regulated by histone posttranslational modifications. Hence, this review will provide a timely update on the possible mechanism(s) converging towards BIR induce AD and PD. Further, emphasis on the potential epigenetic regulation of autophagy that can be effectively targeted for devising a complete therapeutic cure for BIR-induced AD and PD will also be reviewed.

Different Effects and Mechanisms of Selenium Compounds in Improving Pathology in Alzheimer’s Disease

Owing to the strong antioxidant capacity of selenium (Se) in vivo, a variety of Se compounds have been shown to have great potential for improving the main pathologies and cognitive impairment in Alzheimer's disease (AD) models. However, the differences in the anti-AD effects and mechanisms of different Se compounds are still unclear. Theoretically, the absorption and metabolism of different forms of Se in the body vary, which directly determines the diversification of downstream regulatory pathways. In this study, low doses of Se-methylselenocysteine (SMC), selenomethionine (SeM), or sodium selenate (SeNa) were administered to triple transgenic AD (3× Tg-AD) mice for short time periods. AD pathology, activities of selenoenzymes, and metabolic profiles in the brain were studied to explore the similarities and differences in the anti-AD effects and mechanisms of the three Se compounds. We found that all of these Se compounds significantly increased Se levels and antioxidant capacity, regulated amino acid metabolism, and ameliorated synaptic deficits, thus improving the cognitive capacity of AD mice. Importantly, SMC preferentially increased the expression and activity of thioredoxin reductase and reduced tau phosphorylation by inhibiting glycogen synthase kinase-3 beta (GSK-3β) activity. Glutathione peroxidase 1 (GPx1), the selenoenzyme most affected by SeM, decreased amyloid beta production and improved mitochondrial function. SeNa improved methionine sulfoxide reductase B1 (MsrB1) expression, reflected in AD pathology as promoting the expression of synaptic proteins and restoring synaptic deficits. Herein, we reveal the differences and mechanisms by which different Se compounds improve multiple pathologies of AD and provide novel insights into the targeted administration of Se-containing drugs in the treatment of AD.

Quercetin 3-O-(6″-O-E-caffeoyl)-β-D-glucopyranoside, a Flavonoid Compound, Promotes Melanogenesis through the Upregulation of MAPKs and Akt/GSK3β/β-Catenin Signaling Pathways.

Quercetin 3-O-(6″-O-E-caffeoyl)-β-D-glucopyranoside is a flavonoid compound produced by various plants with reported antiprotozoal potential against E. histolytica and G. lamblia; however, its effects on skin pigment regulation have not been studied in detail. In this investigation, we discovered that quercetin 3-O-(6″-O-E-caffeoyl)-D-glucopyranoside (coded as CC7) demonstrated a more increased melanogenesis effect in B16 cells. CC7 exhibited no cytotoxicity or effective stimulating melanin content or intracellular tyrosinase activity. This melanogenic-promoting effect was accompanied by activated expression levels of microphthalmia-associated transcription factor (MITF), a key melanogenic regulatory factor, melanogenic enzymes, and tyrosinase (TYR) and tyrosinase-related protein-1 (TRP-1) and 2 (TRP-2) in the CC7-treated cells. Mechanistically, we found that CC7 exerted melanogenic effects by upregulating the phosphorylation of stress-regulated protein kinase (p38) and c-Jun N-terminal kinase (JNK). Moreover, the CC7 upregulation of phosphor-protein kinase B (Akt) and Glycogen synthase kinase-3 beta (GSK-3β) increased the content of β-catenin in the cell cytoplasm, and subsequently, it translocated into the nucleus, resulting in melanogenesis. Specific inhibitors of P38, JNK, and Akt validated that CC7 promotes melanin synthesis and tyrosinase activity by regulating the GSK3β/β-catenin signaling pathways. Our results support that the CC7 regulation of melanogenesis involves MAPKs and Akt/GSK3β/β-catenin signaling pathways.

Mood and behavior regulation: interaction of lithium and dopaminergic system.

Lithium is one of the most effect mood-stabilizing drugs prescribed especially for bipolar disorder. Lithium has wide range effects on different molecular factors and neural transmission including dopaminergic signaling. On the other hand, mesolimbic and mesocortical dopaminergic signaling is significantly involved in the pathophysiology of neuropsychiatric disorders. This review article aims to study lithium therapeutic mechanisms, dopaminergic signaling, and the interaction of lithium and dopamine. We concluded that acute and chronic lithium treatments often reduce dopamine synthesis and level in the brain. However, some studies have reported conflicting results following lithium treatment, especially chronic treatment. The dosage, duration, and type of lithium administration, and the brain region selected for measuring dopamine level were not significant differences in different chronic treatments used in previous studies. It was suggested that lithium has various mechanisms affecting dopaminergic signaling and mood, and that many molecular factors can be involved, including brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB), β-catenin, protein kinase B (Akt), and glycogen synthase kinase-3 beta (GSK-3β). Thus, molecular effects of lithium can be the most important mechanisms of lithium that also alter neural transmissions including dopaminergic signaling in mesolimbic and mesocortical pathways.

Macrophage Inactivation by Small Molecule Wedelolactone via Targeting sEH for the Treatment of LPS-Induced Acute Lung Injury.

Soluble epoxide hydrolase (sEH) plays a critical role in inflammation by modulating levels of epoxyeicosatrienoic acids (EETs) and other epoxy fatty acids (EpFAs). Here, we investigate the possible role of sEH in lipopolysaccharide (LPS)-mediated macrophage activation and acute lung injury (ALI). In this study, we found that a small molecule, wedelolactone (WED), targeted sEH and led to macrophage inactivation. Through the molecular interaction with amino acids Phe362 and Gln384, WED suppressed sEH activity to enhance levels of EETs, thus attenuating inflammation and oxidative stress by regulating glycogen synthase kinase 3beta (GSK3β)-mediated nuclear factor-kappa B (NF-κB) and nuclear factor E2-related factor 2 (Nrf2) pathways in vitro. In an LPS-stimulated ALI animal model, pharmacological sEH inhibition by WED or sEH knockout (KO) alleviated pulmonary damage, such as the increase in the alveolar wall thickness and collapse. Additionally, WED or sEH genetic KO both suppressed macrophage activation and attenuated inflammation and oxidative stress in vivo. These findings provided the broader prospects for ALI treatment by targeting sEH to alleviate inflammation and oxidative stress and suggested WED as a natural lead candidate for the development of novel synthetic sEH inhibitors.

Identifying potent inhibitors against GSK-3β for Non- Small Cell Lung Carcinoma: Molecular modelling approach, ADME/ pharmacokinetics profiling and statistical significance

Glycogen synthase Kinase-3 beta (GSK-3β) has been reported as an important drug target in an array of human diseases including cancer due to its diverse role in numerous signaling pathways.GSK-3β regulates the WNT/β catenin signaling pathway which in response activates the genes which are regulated by T-cell factor/Lymphoid enhancer factor involved in tumorigenesis and malignancy. The phosphorylated GSK-3β Serine 9 is engaged with histogenesis of various non-small cell lung carcinomas (NSCLCs) as compared to small cell lung cancer. In this study, to check the activity of inhibitor against GSK 3β for non- small cell lung cancer, we have selected thirty-three compounds against carboplatin as a reference which shows good anticancer and antidiabetic properties. These compounds were utilized for the molecular docking by using Autodock 4 and further subjected to ADME/pharmacokinetics analysis. The results of study showed that the molecules with ZINC id- 3874496, 3875687, 7996283, 73683137, 2563085, 1306071, 21011059, have the best docking scores and ADME profile. Thus, these compounds can serve as an excellent candidate for drug development against GSK-3β in NSCLC patients. This study investigates the binding of druglike molecules to GSK-3β and has reported that residue Arg141 may be targeted for therapy in NSCLC patients. Further, statistical analysis (T- test) demonstrates that results are highly significant.

Association study to evaluate Foxo1 and Foxo3 gene polymorphisms in polycystic ovary syndrome: a preliminary case-control study and in silico analysis.

Polycystic ovary syndrome (PCOS) is known as a multifactorial and multi-gene-mediated endocrine disorder among women of reproductive age. FoxO1 and FoxO3 are members of the forkhead transcriptional factors family that play a pivotal role in the function of ovaries. The current work is aimed at investigating the association between gene variants of FoxO1 and FoxO3 and the risk of PCOS in a sample of the Iranian population. We recruited 200 women diagnosed with PCOS and 200 healthy women. Both polymerase PCR-RFLP and ARMS-PCR methods were used for genotyping. Sanger sequencing was recruited to confirm the genotypingresults. The T allele of rs17592236 and the C allele of rs12585277 decreased PCOS risk by 29 and 28%, respectively. In contrast, the C allele of rs2253310 and G allele of rs2802292 increasedthe risk of PCOS by 1.39 and 1.63 folds, correspondingly. Bioinformatics results showed that some genes, including matrix metallopeptidase 9 (MMP-9), phosphoinositide-3-Kinase Regulatory Subunit 224 1 (PIK3R1), peroxisome proliferator-activated receptor Gamma (PPARG), and glycogen synthase 225 kinase-3 beta (GSK-3 beta) have significant interactions with FoxO1, suggesting that FoxO1 might have crucial roles in regulating different signaling pathways in ovarian cells. We found that FoxO1 rs17592236C > T and rs12585277C > T had a protective role against PCOS, while FoxO3 rs2253310C > G and rs2802292G > T enhanced the risk of this metabolic disorder in our population. Additional studies on larger populations with varying racesare needed to confirm these findings.

Blood and cerebrospinal fluid biomarker changes in patients with HIV-associated neurocognitive impairment treated with lithium: analysis from a randomised placebo-controlled trial

HIV-associated neurocognitive disorders (HAND) persist in the era of antiretroviral therapy (ART). Thus, ART does not completely halt or reverse the pathological processes behind HAND. Adjuvant mitigating treatments are, therefore, prudent. Lithium treatment is known to promote neuronal brain–derived neurotrophic factors (BDNF). Lithium is also an inhibitor of glycogen synthase kinase-3 beta (GSK-3-β). We analyzed biomarkers obtained from participants in a randomized placebo-controlled trial of lithium in ART-treated individuals with moderate or severe HAND. We assayed markers at baseline and 24 weeks across several pathways hypothesized to be affected by HIV, inflammation, or degeneration. Investigated biomarkers included dopamine, BDNF, neurofilament light chain, and CD8 + lymphocyte activation (CD38 + HLADR +). Alzheimer’s Disease (AD) biomarkers included soluble amyloid precursor protein alpha and beta (sAPPα/β), Aβ38, 40, 42, and ten other biomarkers validated as predictors of mild cognitive impairment and progression in previous studies. These include apolipoprotein C3, pre-albumin, α1-acid glycoprotein, α1-antitrypsin, PEDF, CC4, ICAM-1, RANTES, clusterin, and cystatin c. We recruited 61 participants (placebo = 31; lithium = 30). The age baseline mean was 40 (± 8.35) years and the median CD4 + T-cell count was 498 (IQR: 389–651) cells/μL. Biomarker concentrations between groups did not differ at baseline. However, both groups’ blood dopamine levels decreased significantly after 24 weeks (adj. p < 002). No other marker was significantly different between groups, and we concluded that lithium did not confer neuroprotection following 24 weeks of treatment. However, the study was limited in duration and sample size.

SAMD9 Promotes Postoperative Recurrence of Esophageal Squamous Cell Carcinoma by Stimulating MYH9-Mediated GSK3β/β-Catenin Signaling.

Recurrence is a challenge to survival after the initial treatment of esophageal squamous cell carcinoma (ESCC). But, its mechanism remains elusive and there are currently no biomarkers to predict postoperative recurrence. Here, the possibility of sterile alpha motif domain-containing protein 9 (SAMD9) as a predictor of postoperative recurrence of ESCC is evaluated and the molecular mechanisms by which SAMD9 promotes ESCC recurrence are elucidated. The authors found that the high level of SAMD9 is correlated with postoperative recurrence and poor prognosis of ESCC. Overexpression of SAMD9 promotes tumor stemness, angiogenesis, and EMT, while downregulation of SAMD9 reduced these phenotypes. Mechanistically, it is found that SAMD9 stimulated ubiquitination-mediated glycogen synthase kinase-3 beta (GSK-3β) degradation by interaction with myosin-9 (MYH9) and TNF receptor-associated factor 6 (TRAF6), which in turn activated Wnt/β-catenin pathway. Further, the authors demonstrated that silencing SAMD9 inhibited lung metastasis and tumor formation in vivo. Finally, the authors found that silencing MYH9 or β-catenin, or overexpressing GSK-3β inhibited SAMD9-stimulated ESCC cell stemness, EMT, angiogenesis, metastasis, and tumorigenicity. Together, the findings indicate that the SAMD9/MYH9/GSK3β/β-catenin axis promotes ESCC postoperative recurrence and that SAMD9 is a crucial target for ESCC therapy. Additionally, SAMD9 has the potential as a predictor of postoperative recurrence in ESCC.

Epigallocatechin-3-gallate alleviates gestational stress-induced postpartum anxiety and depression-like behaviors in mice by downregulating semaphorin3A and promoting GSK3β phosphorylation in the hippocampus.

Postpartum depression (PPD) is a common neuropsychiatric disorder characterized by depression and comorbid anxiety during the postpartum period. PPD is difficult to treat because of its elusive mechanisms. Epigallocatechin-3-gallate (EGCG), a component of tea polyphenols, is reported to exert neuroprotective effects in emotional disorders by reducing inflammation and apoptosis. However, the effect of EGCG on PPD and the underlying mechanism are unknown. We used a mouse model of PPD established by exposing pregnant mice to gestational stress. Open field, forced swimming and tail suspension tests were performed to investigate the anxiety and depression-like behaviors. Immunohistochemical staining was used to measure the c-fos positive cells. The transcriptional levels of hippocampal semaphorin3A(sema3A), (glycogen synthase kinase 3-beta)GSK3β and collapsin response mediator protein 2(CRMP2) were assessed by RT-PCR. Alterations in protein expression of Sema3A, GSK3β, p-GSK3β, CRMP2 and p-CRMP2 were quantified by western blotting. EGCG was administrated to analyze its effect on PPD mice. Gestational stress induced anxiety and depression-like behaviors during the postpartum period, increasing Sema3A expression while decreasing that of phosphorylated GSK3β as well as c-Fos in the hippocampus. These effects were reversed by systemic administration of EGCG. Thus, EGCG may alleviate anxiety and depression-like behaviors in mice by downregulating Sema3A and increasing GSK3β phosphorylation in the hippocampus, and has potential application in the treatment of PPD.

Slit2/Robo1 signaling inhibits small-cell lung cancer by targeting β-catenin signaling in tumor cells and macrophages.

Small-cell lung cancer (SCLC) is an aggressive neuroendocrine subtype of lung cancer with poor patient prognosis. However, the mechanisms that regulate SCLC progression and metastasis remain undefined. Here, we show that the expression of the slit guidance ligand 2 (SLIT2) tumor suppressor gene is reduced in SCLC tumors relative to adjacent normal tissue. In addition, the expression of the SLIT2 receptor, roundabout guidance receptor 1 (ROBO1), is upregulated. We find a positive association between SLIT2 expression and the Yes1 associated transcriptional regulator (YAP1)-expressing SCLC subtype (SCLC-Y), which shows a better prognosis. Using genetically engineered SCLC cells, adenovirus gene therapy, and preclinical xenograft models, we show that SLIT2 overexpression or the deletion of ROBO1 restricts tumor growth in vitro and in vivo. Mechanistic studies revealed significant inhibition of myeloid-derived suppressor cells (MDSCs) and M2-like tumor-associated macrophages (TAMs) in the SCLC tumors. In addition, SLIT2 enhances M1-like and phagocytic macrophages. Molecular analysis showed that ROBO1 knockout or SLIT2 overexpression suppresses the transforming growth factor beta 1 (TGF-β1)/β-catenin signaling pathway in both tumor cells and macrophages. Overall, we find that SLIT2 and ROBO1 have contrasting effects on SCLC tumors. SLIT2 suppresses, whereas ROBO1 promotes, SCLC growth by regulating the Tgf-β1/glycogen synthase kinase-3 beta (GSK3)/β-catenin signaling pathway in tumor cells and TAMs. These studies indicate that SLIT2 could be used as a novel therapeutic agent against aggressive SCLC.

Intrarenal and Urinary Glycogen Synthase Kinase-3 Beta Levels in Diabetic and Nondiabetic Chronic Kidney Disease

Background: Renal glycogen synthase kinase-3 beta (GSK3β) overactivity has been associated with a diverse range of kidney diseases. GSK3β activity in urinary exfoliated cells was reported to predict the progression of diabetic kidney disease (DKD). We compared the prognostic value of urinary and intrarenal GSK3β levels in DKD and nondiabetic chronic kidney disease (CKD). Methods: We recruited 118 consecutive biopsy-proved DKD patients and 115 nondiabetic CKD patients. Their urinary and intrarenal GSK3β levels were measured. They were then followed for dialysis-free survival and rate of renal function decline. Results: DKD group had higher intrarenal and urinary GSK3β levels than nondiabetic CKD (p < 0.0001 for both), but their urinary GSK3β mRNA levels were similar. Urinary p-GSK3β level is statistically significantly correlated with the baseline estimated glomerular filtration rate (eGFR), but urinary GSK3β level by ELISA, its mRNA level, the p-GSK3β level, or the p-GSK3β/GSK3β ratio had no association with dialysis-free survival or the slope of eGFR decline. In contrast, the intrarenal pY216-GSK3β/total GSK3β ratio significantly correlated with the slope of eGFR decline (r = −0.335, p = 0.006) and remained an independent predictor after adjusting for other clinical factors. Conclusion: Intrarenal and urinary GSK3β levels were increased in DKD. The intrarenal pY216-GSK3β/total GSK3β ratio was associated with the rate of progression of DKD. The pathophysiological roles of GSK3β in kidney diseases deserve further studies.

Protective effect of Capsosiphon fulvescens on oxidative stress-stimulated neurodegenerative dysfunction of PC12 cells and zebrafish larva models

Reactive oxygen species (ROS) at high concentrations induce oxidative stress, an imbalanced redox state that is a prevalent cause of neurodegenerative disorders. This study aimed to investigate the protective effect of Capsosiphon fulvescens (CF) extract on oxidative stress-induced impairment of cognitive function in models of neurodegenerative diseases. CF was extracted with subcritical water and several solvents and H2O2 (0.25 mM) or aluminum chloride (AlCl3; 25 μM) as an inducer of ROS was treated in PC12 neuronal cells and zebrafish larvae. All statistical analyses were performed using one-way analysis of variance and Dunnett’s test using GraphPad Prism. H2O2 and AlCl3 were found to significantly induce ROS production in PC12 neuronal cells and zebrafish larvae. In addition, they strongly affected intracellular Ca2+ levels, antioxidant enzyme activity, brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) signaling, acetylcholinesterase (AChE) activity, and hallmarks of Alzheimer’s disease. However, treatment of H2O2-induced PC12 cells or AlCl3-induced zebrafish larvae with CF subcritical water extract at 90°C and CF water extract effectively regulated excessive ROS production, intracellular Ca2+ levels, and mRNA expression of superoxide dismutase, glutathione peroxide, glycogen synthase kinase-3 beta, β-amyloid, tau, AChE, BDNF, and TrkB. Our study suggested that CF extracts can be a potential source of nutraceuticals that can improve the impairment of cognitive function and synaptic plasticity by regulating ROS generation in neurodegenerative diseases.

Potential Regulatory Role of miR-21 on Alzheimer's Disease by Targeting GSK-3β Signaling.

Alzheimer's disease (AD) is the most important neurogenerative disorder with progressive dementia as its main clinical manifestation. The microRNAs (miRNAs) are identified as crucial modulators in AD progression. Nevertheless, the biological potential of miR-21 in AD is obscure. Hence, this study aimed to evaluate the possible role of miR-21 in the pathogenesis of AD via phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (AKT)/glycogen synthase kinase-3beta (GSK-3β) signaling. The miR-21 expression in the brain tissues of patients with AD, as well as normal brain tissues and Aβ1-42-stimulated SH-SY5Y cell line (AD model) was examined by in situ hybridization and quantitative real-time polymerase chain reaction. Also, the apoptosis-linked protein levels as well as programmed cell death 4 (PDCD4) were detected by western blot. Our findings revealed that miR-21 was low expressed in the brain tissues of patients with AD and AD model (P0.01). Also, the miR-21 overexpression could inhibit apoptosis of the AD model (P0.01). Indeed, the miR-21 negatively regulated PDCD4 expression, which led to activated PI3K/AKT/GSK-3β signaling. Our study demonstrated that miR-21 cloud inhibits cell apoptosis in AD through the activation of PI3K/AKT/GSK-3β signaling pathway using inhibition of PDCD4 expression.

Seselin promotes cisplatin-induced apoptosis of AGS gastric cancer cells by inhibiting β-catenin expression

Gastric cancer is a commonly diagnosed form of cancer, and cisplatin is commonly used as a chemotherapy drug for treating it. However, the side effects of cisplatin may reduce patients? willingness to use it. Seselin, a derivative of coumarin, has been found to have anticancer properties as well as anticoagulant effects. In this study, we investigated the effect of seselin on promoting cisplatin-induced gastric cancer cell death using the cell proliferation reagent WST-1, BrdU incorporation and lactate dehydrogenase release. The role of seselin and cisplatin in the apoptosis of gastric cancer cells was analyzed using a phospho-kinase array and Western blot analysis. Seselin did not affect G2/M stasis, but it promoted cell death in AGS cells treated with cisplatin. Phospho-kinase array analysis revealed that cisplatin regulates intracellular p53 phosphorylation, while seselin regulates intracellular ?-catenin expression by affecting the phosphorylation of glycogen synthase kinase-3 beta (GSK-3?), extracellular-signal-regulated kinase (ERK) and Src tyrosine kinase. Seselin and cisplatin promote the apoptosis of gastric cancer cells by the synergistic effect of two distinct signaling pathways. These findings suggest that seselin may be used as a complementary therapy to reduce the clinical dose of chemotherapy.